The present invention relates generally to snap-mated bolt seals, security pins and like devices (hereinafter broadly referred to as xe2x80x9csecurity pinsxe2x80x9d) of a general type having an enlarged head and an elongated stem extending from the head, wherein the stem is securely held within a female part when the device is used to securely couple components together in a manner which prevents removal of the security pin except by means destructive to the security pin and/or the mating female part. More specifically, the present invention relates to a puller tool for use in separating a security pin from a female part with which the security pin is mated. The verb xe2x80x9cseparatexe2x80x9d and forms thereof, as used herein in connection with a security pin and female part with which the security pin is mated, shall mean both a nondestructive removal of the security pin from mating with the female part as well as a destructive removal of a portion of the security pin or female part to destroy the locking function of the security pin/female part assembly.
Security pins are well-known locking devices comprising an elongated stem and an enlarged head at an end of the stem. Security pins typically work in combination with a female part having an axially extending hole for receiving the pin stem. The internal wall of the hole and the external wall of the pin stem are configured to provide snap-locking coupling of the security pin and female part when the stem is inserted beyond a predetermined axial distance, whereby axially directed withdrawal of the security pin is prevented. Typically, the pin stem is passed through aligned holes in one or more components and then snap-mated with the female part, thereby preventing separation of the locked component(s). As will be appreciated, the female part or security pin may already be integral with a primary component, such that mating serves to attach another component to the primary component. When the security pin is snap-locked with the female part, the enlarged head of the security pin and the female part snuggly confine the locked components together such that access to the stem of the security pin is not available for cutting or other tampering.
In security pin connections of the type described, the security pin head and/or the female part commonly includes a frusto-conical outer surface portion tapered toward the mating part to allow limited access for exerting axially directed force sufficient to separate the mated security pin and female part. It is known to use three-fingered puller tools, hydraulic rams and presses, and custom centerbolt/plate devices for exerting large axially directed forces to cause separation. These devices are cumbersome, expensive, and potentially dangerous if not used in a careful manner.
Therefore, it is an object of the present invention to provide a puller tool for security pins that is relatively small, inexpensive, and safe to operate.
It is another object of the present invention to provide a puller tool for security pins that accepts an electric, pneumatic, or hydraulic torque wrench and converts the applied torque to an axially directed separation force.
In furtherance of these and other objects, a puller tool for separating a security pin having an enlarged security pin head from a female part with which the security pin is mated generally comprises an outer sleeve having an axially extending passage, an actuating bolt including an enlarged head and a threaded shank axially insertable into the passage, a radial detent shoulder arranged to engage the head of the actuating bolt to prevent insertion of the bolt head into the passage of the outer sleeve, and a puller member insertable into the passage from an opposite end of the sleeve. The puller member is axially slidable relative to the outer sleeve by rotation of the actuating bolt which mates with a threaded hole in the puller member, and the puller member is prevented from rotating relative to the outer sleeve at least when the puller member is fully inserted into the passage. The puller member includes a cavity extending axially and radially through an end thereof. The cavity is configured to receive the security pin head or female part such that the security pin head or female part is removable from the cavity by radially directed but not axially directed extraction.
The puller tool is used by sliding the puller tool radially over a security pin head or female part so that the security pin head or female part is received within the cavity of the puller member, and applying torque to the head of the actuating bolt using a pneumatic torque wrench or the like. A distal end of the outer sleeve bears against one of the locked components, and the puller member is drawn axially further into the passage by rotation of the actuating bolt to load the security pin in tension until the security pin fails.